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1.
J Enzyme Inhib Med Chem ; 38(1): 2274798, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37905438

RESUMO

Type 2 diabetes (T2D) is a progressive metabolic disorder of glucose metabolism. One of the therapeutic approaches for the treatment of T2D is reducing postprandial hyperglycaemia through inhibition of the digestive enzymes α-glucosidase and α-amylase. In this context, aimed at identifying natural products endowed with anti-T2D potential, we focused on Ptilostemon casabonae (L.) Greuter, a species belonging to Asteraceae family. Enzymatic inhibition, antioxidant activity, phenolic composition and cellular assays were performed. This study revealed that the P. casabonae hydroalcoholic extract exerts a potent inhibitory activity against α-glucosidase. This activity is supported by an antioxidant effect, preventing ROS formation in a stressed cellular system. HPLC-PDA-MS/MS analysis, revealed a complex polyphenolic fraction. Among the tested pure compounds, 1,5-dicaffeoylquinic acid, apigenin and rutin displayed good α-glucosidase inhibitory activity. Our study suggested new potential of P. casabonae encouraging us to further testing the possible therapeutic potential of this extract.


Assuntos
Asteraceae , Diabetes Mellitus Tipo 2 , Diabetes Mellitus Tipo 2/tratamento farmacológico , Antioxidantes/farmacologia , Hipoglicemiantes/farmacologia , Inibidores de Glicosídeo Hidrolases/farmacologia , alfa-Glucosidases/metabolismo , Extratos Vegetais/farmacologia , Espectrometria de Massas em Tandem , alfa-Amilases/metabolismo
2.
Plants (Basel) ; 11(23)2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36501354

RESUMO

As they represent actual or potential risks to human and environmental safety and health, abandoned mines are a major global problem. The heavy metal-polluted tailings dump of Barraxiutta (Domusnovas, southwestern Sardinia, Italy) is home to a metallicolous population of Epipactis tremolsii (Orchidaceae). A reclamation of the abandoned mine area seems to be approaching, and such an intervention may pose a serious risk for the maintenance of the unique orchid population colonizing the mine wastes. In the present work, the seed packet technique was implemented for the first time to observe orchid seed development in mine wastes. This approach allowed us to explore different seed-based conservation options for the metallicolous orchid population and to gain a deeper grasp of population dynamics and ecology. Four different sowing treatments were set up in the tailing dump and in a near unpolluted site (control site). The field phase of the experiment lasted for 10 months, a period in which the experimental seed bank preservation and incipient seed development were observed and statistically approached. Our findings observed no significant seed loss happening during the experiment, demonstrating the suitability of the seed packet technique to also explore seed bank conservation and development in extreme environmental conditions (i.e., polluted mine wastes). This field method will be a useful tool to further explore the more effective translocation and quasi in situ conservation alternatives for the E. tremolsii metallicolous population. Incipient and site-specific seed development (non-mycorrhizal stage) was observed during the experiment. A plant-soil fungus interaction at the seed level was also observed, the nature of which remains to be ascertained in further studies providing a longer duration for the field phases.

3.
Anal Chem ; 94(29): 10435-10442, 2022 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-35848818

RESUMO

The need to find a rapid and worthwhile technique for the in situ detection of the content of delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) in Cannabis sativa L. is an ever-increasing problem in the forensic field. Among all the techniques for the detection of cannabinoids, Raman spectroscopy can be identified as the most cost-effective, fast, noninvasive, and nondestructive. In this study, 42 different samples were analyzed using Raman spectroscopy with 1064 nm excitation wavelength. The use of an IR wavelength laser showed the possibility to clearly identify THC and CBD in fresh samples, without any further processing, knocking out the contribution of the fluorescence generated by visible and near-IR sources. The results allow assigning all the Raman features in THC- and CBD-rich natural samples. The multivariate analysis underlines the high reproducibility of the spectra and the possibility to distinguish immediately the Raman spectra of the two cannabinoid species. Furthermore, the ratio between the Raman bands at 1295/1440 and 1623/1663 cm-1 is identified as an immediate test parameter to evaluate the THC content in the samples.


Assuntos
Canabidiol , Canabinoides , Cannabis , Canabinoides/análise , Cannabis/química , Dronabinol/análise , Reprodutibilidade dos Testes , Análise Espectral Raman
4.
Plants (Basel) ; 11(6)2022 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-35336708

RESUMO

Orchidaceae is a flowering plant family worldwide distributed known for producing volatile organic compounds (VOCs) which can act as olfactory signals for pollinators. Despite the importance of VOCs in the different reproductive strategies, in the literature there are only a few publications on the characterization of orchids' volatile profiles. In this study, the essential oils from fresh inflorescences of sympatric orchids Anacamptis morio, Himantoglossum robertianum, Ophrys sphegodes and Orchis purpurea, naturally growing in Piedmont (Italy) were isolated by steam distillation and characterized by GC/FID and GC/MS. A number of compounds were identified, with a peculiar distribution in the species: alcohols (range 16.93-50.60%), from which p-cresol (range 12.75-38.10%) was the most representative compound; saturated hydrocarbons (range 5.81-59.29%), represented by pentacosane (range 2.22-40.17%) and tricosane (range 0.78-27.48%); long-chain monounsaturated hydrocarbons (range 0.29-5.20%) represented by 9-pentacosene, 11-tricosene, and 1-heneicosene. The structure of positional isomers in linear alkenes was elucidated by derivatization with dimethyl disulfide and MS fragmentation patterns. Coumarin (68.84%) was the dominant compound in O. purpurea and was detected in lower concentrations (range 0.21-0.26%) in the other taxa. These volatile compounds may represent a particular feature of these plant species and play an essential role in pollinator interaction.

5.
Front Plant Sci ; 11: 563971, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33133114

RESUMO

Seed's maturity and integrity are essential requirements for germination, and they rely on nutrients availability and a correct phytohormones' balance. These aspects are prerequisites for prompt germination at the end of the dormancy period and strictly depend on chloroplast metabolism and photosynthesis. In the present work, capsules of Nicotiana tabacum were grown in dark during the whole post-anthesis period. Among others, photosynthetic rates, dormancy, and phytohormones levels in seeds were found to be significantly different with respect to controls. In particular, etiolated capsules had expectedly reduced photosynthetic rates and, when compared to controls, their seeds had an increased mass and volume, an alteration in hormones level, and a consequently reduced dormancy. The present findings show how, during fruit development, the presence of light and the related fruit's photosynthetic activity play an indirect but essential role for reaching seeds maturity and dormancy. Results highlight how unripe fruits are versatile organs that, depending on the environmental conditions, may facultatively behave as sink or source/sink with associated variation in seed's reserves and phytohormone levels.

6.
Plants (Basel) ; 9(11)2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33238580

RESUMO

Analysis of the seed morphology is a widely used approach in ecological and taxonomic studies. In this context, intraspecific variability with respect to seed morphology (size, weight, and density) was assessed in two close Epipactis tremolsii Pau. populations sharing the same ecological conditions, except for the soil pollution distinguishing one of them. Larger and heavier seeds were found in plants growing on the heavy metal polluted site, while no differences in seed density were detected between seeds produced by plants growing on the contaminated and the control site. Moreover, seed coats and embryos varying together in their dimensions were described in the control population, while coats varying in their size independently from embryos were described in plants growing on the polluted site. Seeds from the two studied populations significantly differed in several parameters suggesting that intraspecific seed variability occurred in the case study.

7.
Ecotoxicol Environ Saf ; 189: 110018, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31812823

RESUMO

Understanding how environmental pollutants influence plant occurrence, growth, and development is key for effective management plans and potential bioremediation. Rare plants, such as orchids, may occur in modified habitats and on soils containing heavy metals, yet their ecological and physiological responses to heavy metals is poorly understood. We investigated the influence of heavy metal pollution on orchid growth rates and interactions with soil fungal mutualists by comparing a large population of the orchid Epipactis helleborine (L.) Crantz subsp. tremolsii (Pau) E. Klein that grows on mine tailings in south-west Sardinia (Italy) with a population that grows on non-contaminated soils in central Sardinia. Soils of the contaminated site had high levels of heavy metals and low organic matter and nutritive elements content. We performed a morphological analysis on twenty individuals that have been subjected to measurement of bioaccumulation and translocation of heavy metals. Fungi associated with the roots of plants from the contaminated and uncontaminated site were grown and identified by DNA barcoding approach. Plants from the contaminated site were smaller than the ones growing in the uncontaminated site and were found to be able to tolerate heavy metals from the soil and to accumulate and translocate them into their organs. Fungi belonging to the genus Ilyonectria (Ascomycota) were found both in contaminated and uncontaminated sites, while an unidentified fungus was isolated from roots in the contaminated site only. These results are discussed in terms of orchids' tolerance to heavy metals and its physiological and ecological mechanisms. The role of contaminated habitats in harbouring orchids and peculiar taxa is also discussed.


Assuntos
Metais Pesados/metabolismo , Orchidaceae/metabolismo , Poluentes do Solo/metabolismo , Ascomicetos/classificação , Ascomicetos/isolamento & purificação , Biodegradação Ambiental , Ilhas , Itália , Metais Pesados/análise , Mineração , Orchidaceae/crescimento & desenvolvimento , Orchidaceae/microbiologia , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , Solo/química , Poluentes do Solo/análise
8.
J Nucl Cardiol ; 25(5): 1621-1628, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-28160262

RESUMO

BACKGROUND: Both the myocardial perfusion pattern and myocardial blood flow (MBF) are used to assess patients with suspected coronary artery disease (CAD). The aim of this study was to compare the perfusion pattern (using the summed difference score [SDS]) to MBF in a consecutive group of patients undergoing PET/CT with 13 N-ammonia (13NH3). METHODS: 47 consecutive patients, aged 65 ± 12 years (42 men) with known or suspected CAD, underwent vasodilator stress/rest PET/CT with 13NH3 for clinical indications. The SDS was determined by a commercially available software based on a 17-segment model. MBF was measured at rest and during hyperemia by dynamic acquisition and single-compartment model analysis. From the rest and stress MBF, the absolute difference (stress-rest) in myocardial blood flow defined as difference in myocardial blood flow (DMBF) was derived. RESULTS: There were no significant differences between patients with no ischemia (SDS ≤ 1) and those with ischemia (SDS > 1) in CFR (2.84 ± 0.73 vs 2.63 ± 0.89, P = NS) and DMBF (1.34 ± 0.45 vs 1.24 ± 0.53 mL·minute-1·g-1, P = NS). There were however significant regional differences (141 different vascular territories in 47 patients) between these two groups (CFR: 2.84 ± 0.95 vs 2.16 ± 0.57, P < .001 and DMBF: 1.39 ± 0.6 vs 0.87 ± 0.39, P < .0001). The correlation between regional CFR and regional DMBF with SDS was significant (y = 2.7145e-0.059x R = 0.358 and y = 1.2769e-0.119x R = 0.44) CONCLUSION: The SDS is the difference between two measurements (stress-rest) and it correlates better with regional DMBF, which is another measurement that reflects the difference between stress and rest. The correlation is better on regional than global basis.


Assuntos
Doença da Artéria Coronariana/fisiopatologia , Circulação Coronária , Imagem de Perfusão do Miocárdio/métodos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Amônia , Doença da Artéria Coronariana/diagnóstico por imagem , Feminino , Reserva Fracionada de Fluxo Miocárdico , Humanos , Masculino , Pessoa de Meia-Idade , Radioisótopos de Nitrogênio
9.
Nucl Med Commun ; 37(4): 412-21, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26637072

RESUMO

OBJECTIVE: PET radiopharmaceuticals are often injected in patients before all quality controls are performed and before sterility results are available. We propose a process validation to produce very safe and pure [N]NH3 for human use. METHODS: [N]NH3 was produced in the cyclotron target. Online purification was performed by anionic exchange resin. All the production steps were subjected to a sterility test. Some additional controls were added to those required by the monograph. RESULTS: The radiochemical yield of the syntheses was 26.3 and 61.5% corrected for decay, with a radiochemical purity of 100%. In addition to quality controls requested by the European Pharmacopeia monograph, we carefully analyzed the product for the presence of possible contaminants. Some elements, mainly metals, were found in very low amounts at concentrations in the range of ppb. The radionuclidic purity was verified. The achievement of the parameters of osmolality, by addition of saline solution to the preparation, made the analysis of chemical purity difficult and worsened the measurement of radiochemical purity by high performance liquid chromatography. Only pH control is necessary before administration to patients and therefore a safe production process was set up to prevent microbiological contamination. All phases were carefully standardized, starting from in-target production of [N]NH3, to final splitting in the syringes. Sterility tests showed no bacterial growth, indicating the safety of the production process. CONCLUSION: All our syntheses followed the monograph indications and were optimal to obtain PET imaging of a patient's myocardium.


Assuntos
Amônia/química , Radioisótopos de Nitrogênio , Radioquímica/métodos , Compostos Radiofarmacêuticos/química , Humanos , Concentração de Íons de Hidrogênio , Concentração Osmolar , Controle de Qualidade , Solventes/química , Esterilização
10.
Eur J Pediatr ; 170(1): 51-7, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20669028

RESUMO

Although endoscopy with biopsy is the gold standard for the diagnosis of inflammatory bowel disease (IBD), this procedure is invasive and its repetition is stressful, especially in children. The purpose of this study was to evaluate prospectively the role of (99m)Tc-HMPAO-labeled granulocyte scintigraphy in the diagnosis and follow-up of pediatric IBD and its possible use as an alternative to colonoscopy to determine the disease extent and severity beyond its ability to differentiate ulcerative colitis from Crohn's disease. During a 10-year period, 52 children, aging between 2 and 17 years (median, 11.09 years), were subjected to (99m)Tc-HMPAO granulocyte scan 7-28 days from conventional diagnostic tests, and the results were compared with endoscopic and bioptic results. Disease severity was graded by the focal uptake intensity versus iliac bone uptake (Scan Activity Index) and compared with Endoscopy Mayo Score. In 15 out of 16 patients, IBD diagnosis was obtained with a full correspondence of location and severity of lesions, respectively, in 14 out of 16 and 13 out of 16, while in 31 out of 36 patients, IBD was correctly excluded (sensitivity of 93.7%, specificity of 86.1%, and negative predictive value of 96.4%). During the follow-up, all relapses (24) and remissions (13) were correctly recognized (sensibility and specificity of 100%). In conclusion, (99m)Tc-HMPAO granulocyte scan is an accurate minimally invasive technique with very good accuracy, able to diagnose and to grade the intensity and extent of the disease; it is also a useful tool in the follow-up of pediatric IBD where it could reliably replace the invasive endoscopic assessment in most cases.


Assuntos
Granulócitos/diagnóstico por imagem , Doenças Inflamatórias Intestinais/diagnóstico por imagem , Intestinos/diagnóstico por imagem , Tecnécio Tc 99m Exametazima , Adolescente , Biópsia , Criança , Pré-Escolar , Doença Crônica , Diagnóstico Diferencial , Endoscópios Gastrointestinais , Feminino , Seguimentos , Humanos , Masculino , Estudos Prospectivos , Cintilografia
11.
Tumori ; 88(6): 503-6, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12597147

RESUMO

AIMS AND BACKGROUND: The results of several randomized trials and meta-analyses have been reported on adjuvant treatment for early breast cancer and treatment guidelines have been defined accordingly, but detailed data are lacking on the appropriateness of treatment prescription in clinical practice. METHODS: We performed a prospective, observational, multicenter study to monitor the prescription, delivery and effectiveness of radiotherapy following conservative surgery for early breast cancer; 1610 patients treated with postoperative radiation to the breast in 1997 were entered by 12 centers in Lombardy, Italy. Here we report the results of a secondary analysis focused on the prescription of medical adjuvant treatment (1547 eligible patients). RESULTS: Chemotherapy only was prescribed to 526 patients (33%), hormonal therapy only to 539 (33%), and both treatments to 85 patients (5%); 460 women (29%) received no medical adjuvant treatment. We compared the collected data with guidelines defined in 1995 by the St Gallen Consensus Conference. Undertreatment was most frequent in node-negative patients at intermediate/high risk, no treatment (instead of tamoxifen or chemotherapy) being prescribed in 21-45% of cases. Node-negative patients at low risk, on the other hand, were overtreated with tamoxifen in 31% of cases. In node-positive, premenopausal women compliance with guidelines was far better, with a 91-96% rate of chemotherapy prescription. In node-positive, postmenopausal, estrogen receptor-positive patients chemotherapy was unduly prescribed in as many as 56% of cases. Comparison of clinical practice with the next version of the guidelines (1998) showed a somewhat better compliance. CONCLUSIONS: Despite the availability of official and authoritative guidelines, adjuvant treatment prescription for early breast cancer in Lombardy in 1997 was suboptimal, especially in well-defined subgroups of patients.


Assuntos
Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Quimioterapia Adjuvante , Fidelidade a Diretrizes/estatística & dados numéricos , Padrões de Prática Médica/estatística & dados numéricos , Radioterapia Adjuvante , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/radioterapia , Prescrições de Medicamentos/estatística & dados numéricos , Feminino , Humanos , Cooperação Internacional , Itália , Metástase Linfática , Menopausa , Pessoa de Meia-Idade , Observação , Guias de Prática Clínica como Assunto , Estudos Prospectivos , Medição de Risco , Fatores de Risco
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